22 May 2008
Cooling load in winter season is significant in many commercial buildings and hotels because of the usage of office equipments and efficient wall insulation. The development of a multi-heat pump that can cover heating and cooling simultaneously for each indoor unit is required. In this study, a 4-room simultaneous heating and cooling heat pump system was designed and its performance including cooling/heating capacity and COP was measured at four operating modes; cooling-only, heating-only, cooling-main, and heating-main modes. The system used R410A as a working fluid and adopted a variable speed compressor and EEV. The experiments were performed by varying outdoor temperature in each operating mode. Problems in the designed heat pump system were analyzed and defined. In addition, the solutions of the problems were suggested to improve system performance and achieve stable operation.